On Tue, 6 Apr 2010, Andrea Arcangeli wrote: > > In short I first measured the page fault improvement in host (~+50% > faster, sure that has nothing to do with pmd_huge or the tlb miss, I > said I mentioned it just for curiosity in fact), then measured the tlb > miss improvement in host (a few percent faster as usual with > hugetlbfs) then measured the boost in guest if host uses hugepages > (with no guest kernel change at all, just the tlb miss going faster in > guest and that boosts the guest kernel compile 6%) and then some other > test with dd with all combinations of host/guest using hugepages or > not, and also with dd run on bare metal with or without hugepages. Yeah, sorry. I misread your email - I noticed that 6% improvement for something that looked like a workload I might actually _care_ about, and didn't track the context enough to notice that it was just for the "host is using hugepages" case. So I thought it was a more interesting load than it was. The virtualization "TLB miss is expensive" load I can't find it in myself to care about. "Get a better CPU" is my answer to that one, Linus -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>